sqs.md

AWS SQS setup

Register an account in AWS

• credit card needed

Get the Access Key

• get in My Security Credentials (at the right top dropdown)
• get in Access keys (access key ID and secret access key)
• create new access key
• copy the credentials
  • NOTE: the credentials is shown only one time except downloading the file

Create a SQS queue

• get in sqs site
• set the region (at the right top dropdown)
  • dev & test: Asia Pacific (Tokyo)ap-northeast-1
  • production(Heroku): US East (N. Virginia)us-east-1 (NOT SURE)
• create queue
  • NOTE: the queue name and type could not change after created
• copy the queue name & queue URL

Test the SQS queue (in irb)

Connect to Queue

require 'aws-sdk-sqs'

sqs = Aws::SQS::Client.new(
    access_key_id: config.AWS_ACCESS_KEY_ID,
    secret_access_key: config.AWS_SECRET_ACCESS_KEY,
    region: config.AWS_REGION
)

q_url = sqs.get_queue_url(queue_name: 'your_queue_name').queue_url
queue = Aws::SQS::Queue.new(url: q_url, client: sqs)

Publisher: Send Messsage

msg = { code: "The time is #{Time.now}"}
queue.send_message(message_body: msg.to_json)

Subscriber: Receive Message Batch

messages = queue.receive_messages
msg = messages.first

# PROCESS THE MESSAGE HERE
JSON.parse(msg.body)

queue.delete_messages(
    entries: [{ 
        id: msg.message_id,
        receipt_handle: msg.receipt_handle
    }])

Poller: Keep receiving messages

poller = Aws::SQS::QueuePoller.new(q_url, client: sqs)

poller.poll do |msg|
    print "MESSAGE: #{JSON.parse msg.body}, "
end